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# Re: views about science survey

• From: Robert A Cohen <bbq@ESU.EDU>
• Date: Tue, 6 Feb 2001 10:02:02 -0500

I agree with JSD. Upon reading choice (a) I thought the question was

True/False? Newton's laws of motion apply to physical objects regardless
of their position in the universe.

...and I figured choice (a) was correct. Then I read choice (b) and I
thought the question was asking something like...

True/False? Newton's laws of motion apply to some physical objects
in the universe but not all.

...and so I figured choice (b) was correct. Then I got stuck. Am I
supposed to be stuck?

----------------------------------------------------------
| Robert Cohen Department of Physics |
| East Stroudsburg University |
| bbq@esu.edu East Stroudsburg, PA 18301 |
| http://www.esu.edu/~bbq/ (570) 422-3428 |
----------------------------------------------------------

On Mon, 5 Feb 2001, John S. Denker wrote:

At 10:47 PM 2/5/01 +0200, Muhsin Ogretme wrote:

12. Physicists' current ideas about particles that make up the atom
apply to:
(a) physical objects that could be anywhere in the universe.
(b) some physical objects in the universe but not others.

13. Newton's laws of motion (like his second law expressed in the
form F = ma) apply to:
(a) physical objects that could be anywhere in the universe.
(b) some physical objects in the universe but not others.

Huh? Those are very strange questions. Are they meant to be trick questions?

For one thing, the questions ask for a dichotomous choice, but the offered
choices are not orthogonal; they are not the halves of a dichotomy. (a)
suggests choosing a position, while (b) suggests choosing one class of
object over another.

I feel like somebody asked me to choose:

99. Sodium is...
(a) Necessary for life.
(b) Dangerously reactive.

Both (a) and (b) are perfectly true. Without more context, there is not
even any way to choose which is a "better" answer.

Returning to the given questions:

12. Physicists' current ideas about particles that make up the atom
apply to:
(a) physical objects that could be anywhere in the universe.
(b) some physical objects in the universe but not others.

SOME ideas about atomic particles apply to atomic particles and not other
objects. For instance, the notion of "carrying electric charge always less
than 200 per particle" applies to atoms and their constituents, but does
not apply to baseballs.

SOME ideas about atomic particles apply to objects that could be anywhere
in the universe. For instance, the notion of "being subject to a local
momentum-conservation law" applies to just about everything everywhere.

So if the opening words "Physicists' ideas" are interpreted as meaning "ALL
physicists' ideas" then both (a) and (b) are false. If those words are
interpreted as "SOME physicists' ideas" then both (a) and (b) are true.

Why would anybody ask such a question? What would anybody conclude from

========

13. Newton's laws of motion (like his second law expressed in the
form F = ma) apply to:
(a) physical objects that could be anywhere in the universe.
(b) some physical objects in the universe but not others.

Another very odd question.

There are certainly objects in the universe to which F=ma does not
apply; photons for instance. So you could argue that (b) is true.

One could argue against (a), saying that there are places in the universe
where there exist no physical objects to which F=ma could apply; the
interior of a neutron star, for instance.

So in some technical sense, (b) is a better answer. But this is pure
pettifoggery, and obscures an important physical principle, namely the
notion that the fundamental laws of physics apply throughout all of space
and time. The applicability (or non-applicability) of F=ma has nothing to
do with position _per se_; if position matters it is only because it is a
proxy for other physically more-significant variables (such as the local
density of neutrons).

Again: why would anybody ask such a question? What could anybody learn by
asking such a question? What could anybody teach by asking such a question?

Are these meant to be object lessons on how to design a bad test?